Tektronix 784A Graphics Tablet User Manual


 
Typical Characteristics
1–24
TDS 684A, TDS 744A, & TDS 784A Service Manual
Table 1–16: Typical Characteristics — Triggering System (Cont.)
Name Description
Width, Minimum Pulse and Rearm, for
Logic Triggering or Events Delay
For vertical settings > 10 mV/div and 1 V/div at the BNC input
Triggering Type
Minimum Pulse
Width
Minimum Re-Arm
Width
Minimum
Time Between
Channels
7
Logic Not Applicable 1 ns 1 ns
Events Delay 1 ns (for either + or
– pulse widths)
Not Applicable 2 ns
Width, Minimum Pulse and Rearm, for
Pulse Triggering
For vertical settings > 10 mV/div. and 3 1 V/div at the BNC input
Width, Minimum Pulse and Rearm, for
Pulse Triggering
The minimum pulse widths and rearm
widths and transition times
8
required for
Pulse Class
Minimum Pulse
Width
Minimum Re-Arm Width
The minimum pulse widths and rearm
widths and transition times
8
required for
Pulse-Type triggering.
Glitch 1 ns 2 ns + 5% of Glitch Width Setting
Pulse-Type triggering.
Runt 2 ns 2 ns
Time-Qualified Runt 2 ns 8.5 ns + 5% of Width Setting
Width 1 ns 2 ns + 5% of Width Upper Limit Setting
Slew Rate 600 ps
8
8.5 ns + 5% of Delta Time Setting
Input Signal Sync Amplitude for Stable
Triggering, HDTV and FLEXFMT modes
(Option 05 Video Trigger)
All field selections: 0.6 division to 4 divisions
Jitter for HDTV mode
(Option 05 Video Trigger)
17 ns
p-p
Sync Width Flex Format and HDTV
modes (Option 05 Video Trigger)
min. 400 ns
Sync Duty Cycle, Flex Format and HDTV
modes (Option 05 Video Trigger)
min. 50 to 1
Hum Rejection
(Option 05 Video Trigger)
NTSC and PAL: –20 dB without any trigger spec deterioration. Triggering will continue
down to 0 dB with some performance deterioration.
1
The trigger position errors are typically less than the values given here. These values are for triggering signals having a
slew rate at the trigger point of 0.5 division/ns.
2
The waveform interval (WI) is the time between the samples in the waveform record. Also, see the footnote for the
characteristics Sample Rate Range or Interpolated Waveform Rates in Table 1–4, on page 1–10.
3
The minimum sensitivity for obtaining a stable trigger. A stable trigger results in a uniform, regular display triggered on
the selected slope. The trigger point must not switch between opposite slopes on the waveform, and the display must not
“roll” across the screen on successive acquisitions. The TRIG’D LED stays constantly lighted when the SEC/DIV setting
is 2 ms or faster but may flash when the SEC/DIV setting is 10 ms or slower.
4
The minimum signal levels required for stable logic or pulse triggering of an acquisition, or for stable counting of a
DC-coupled, events-delay signal. Also, see the footnote for Sensitivity, Edge-Type Trigger, DC Coupled in this table.
(Stable counting of events is counting that misses no events and produces no extra, phantom events.)
5
The minimum signal levels required for stable runt pulse triggering of an acquisition. Also, see the footnote for
Sensitivity, Edge-Type Trigger, DC Coupled in this table. (Stable counting of events is counting that misses no events.)